title: Medication adherence among community-dwelling patients with heart failure.
abstract: OBJECTIVE
  To determine medication use and adherence among community-dwelling patients with heart failure (HF).
  
  
  METHODS
  Residents of Olmsted County, Minnesota, with HF were recruited from October 10, 2007, through February 25, 2009. Pharmacy records were obtained for the 6 months after enrollment. Medication adherence was measured by the proportion of days covered (PDC). A PDC of less than 80% was classified as poor adherence. Factors associated with medication adherence were investigated.
  
  
  RESULTS
  Among the 209 study patients with HF, 123 (59%) were male, and the mean ± SD age was 73.7 ± 13.5 years. The median (interquartile range) number of unique medications filled during the 6-month study period was 11 (8-17). Patients with a documented medication allergy were excluded from eligibility for medication use within that medication class. Most patients received conventional HF therapy: 70% (147/209) were treated with β-blockers and 75% (149/200) with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. Most patients (62%; 127/205) also took statins. After exclusion of patients with missing dosage information, the proportion of those with poor adherence was 19% (27/140), 19% (28/144), and 13% (16/121) for β-blockers, angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, and statins, respectively. Self-reported data indicated that those with poor adherence experienced more cost-related medication issues. For example, those who adhered poorly to statin therapy more frequently reported stopping a prescription because of cost than those with good adherence (46% vs 6%; P < .001), skipping doses to save money (23% vs 3%; P = .03), and not filling a new prescription because of cost (46% vs 6%; P < .001).
  
  
  CONCLUSIONS
  Community-dwelling patients with HF take a large number of medications. Medication adherence was suboptimal in many patients, often because of cost.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
authors.forename: Shannon M
authors.initials: SM
authors.lastname: Dunlay
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Eveleth
authors.forename: Nilay D
authors.initials: ND
authors.lastname: Shah
authors.forename: Sheila M
authors.initials: SM
authors.lastname: McNallan
authors.forename: Véronique L
authors.initials: VL
authors.lastname: Roger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D057911:Angiotensin Receptor Antagonists / Q000627:therapeutic use; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D002318:Cardiovascular Diseases / Q000188:drug therapy; D004358:Drug Therapy / Q000191:economics; D005260:Female; D006333:Heart Failure / Q000188:drug therapy* / Q000191:economics; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors